Control mechanism for door latches



March 29, .1955 E. L. ALLEN CONTROL MECHANISM FOR DOOR LATCHES Original Filed Feb. 16, 1948 4 .w emu IN 29 L 4 I W. M: m W W W D uw w nw w EM i /m\% J1 I/IIVIHV/ A M ATTOPNE'YS f iG. 3

2,705,165 CONTROL MECHANISM FOR DOOR LATCHES Edwin L. Allen, Cleveland Heights, Ohio, assignor, by gifiisne assignments, to Rudolph I. Schonitzer, Cleveland,

Original application February 16, 1948, Serial No. 8,565, now Patent No. 2,573,679, dated November 6, 1951. Divided and this application August 6, 1951, Serial N0.240,524

9 Claims. (Cl. 292-3363) This invention relates to mechanisms and more particularly to certain improvevehicles or the like, it has been proposed to use latch mechanisms of various types. A very successful device for this purpose is illustrated and described in United States Patent No.

Patent No. 2,658,783). In the door control mechanisms illustrated in said patent and application the latching apparatus includes coacting elements associated with the door and door frame structures whereby the door may be latched and held in closed position or released opening thereof, and a dethis operated position until the door is again closed. Means are also provided for locking the mechanism to prevent unauthorized opening of the door, which means effect locking of the door by blocking the detent, together with the parts of the latch mechanism proper which are directly associated with the detent for actuation thereof, against movement from latch restraining to latch released position.

In door control installations of the type referred to, manually operable means is provided, such as a push button or handle assembly, for eflFecting movement of the detent from its latch restraining to its latch released position. In the apparatus of the said Schonitzer patent and of my said copending U. S. patent application such manually operable means is also blocked against movement from its neutral or non-operating position into operating or latch releasing position when the locking means is positioned to block the detent against movement into latch released position. ment is considered undesirable because, if the mechanism is locked and an effort is made to open the door by operating the handle or push button, excessive force may be applied thereon with resulting damage to the latch mechanism, etc. The same difficulty may be encountered in installations of other types of door latches where locking blocks the handle against movement.

Accordingly, it is among the objects of the present invention to provide safety means for permitting the manually operable handle, push button, or the like of a door latching and locking installation to be moved by the operator in its normal path from its neutral or non-operating position to its operating or latch releasing position regardless of whether the latch mechanism, and particularly the part thereof which is directly engaged by the manually operable unit, is free to move or is-locked against movement.

Other objects of my invention include: the provision In some instances this arrange-- of a manually operable control unit for door latches or the like whereby only a predetermined permissible maximum load may be imposed upon the latch mechanism Figure 1 is a horizontal cross-sectional view taken substantially on line 11 of Figure 2, illustrating an embodiment of my invention wherein a single spring acts both as a handle return safety element.

Figure 2 is a side igure 1.

Figure 3 is a vertical cross-sectional view taken substantially on line 3-3 of Figure 2, the parts being seen in their neutral or non-operating positions.

Figure 4 is a vertical cross-sectional viet generally similar to Figure 3 but illustrating the parts in the positions they assume when the latch mechanism is locked and the manually operable handle or the like is moved into operating or latch releasing elevation of the apparatus shown in This actuatmg member is adapted to effect release of tending inwardly at its inner end through a slot 81 in the bezel or supporting frame member 82. The generally hemispherical inner curved washer is slidably mounted on the square bar Referring now to Figures 1 m4, inclusive, the door end portion 83 of handle 79. fits into a corresponding recess 84 inthe bezel 82 and a or lever 80 for engagement with the correspondingly curved inner surface 86 of bezel 82. To maintain washer 85 in frictional sliding engagement with surface 86 a flange 87 is crimped upon or otherwise rigidly secured to the bar 80. A corresponding flange or washer 88 is slidingly mounted on bar 80 in engagement with the outer surface of curved washer 85. Between the washers 87 and 88 is a compression spring 89 which holds the sliding washer 88 against curved washer 85 thus maintaining frictional engagement of washer 85 with the surface 86 of bezel 82 and permitting the handle 79 to have pivotal movement about the vertical center line of the spherical end portion 84 thereof. Such movement of handle 79 may only be in a plane substantially normal to the outer door panel 1 as the recess 81 in bezel 82 has top and bottom edge walls which engage the top and bottom faces of the rectangular bar or lever 80.

The contact member which engages the actuating member or arm 4 of the latch mechanism comprises a lever 90 which is supported at one end on a pin 91, of square cross section, which projects into and is rigidly supported by the inward projection 92 of bezel 82. The lever 90, as is best seen in Figures 3 and 4, is apertured at 93 to accommodate the pin 91 and the cross section of this aperture 93 is sufiiciently larger than the cross section of pin 91 to permit limited swinging movement of lever 90 axially of pin 91 as will be later described. Substantial rotational movement of lever 90 about the axis of pin 91 is prevented by the square cross section of pin 91 and the correspondingly shaped aperture 93 in lever 90.

Supported by the pin 91 and disposed therearound is a combination safety and return spring 94. As seen in Figures 3 and 4, the outer end of this spring 94 abuts the inner face of lever 90 and its inner end abuts a washer 95-which is held in position on the pin 91 as by a nut 96 on the threaded outer end of pin 91. This spring 94 is installed in preloaded or compressed condition and when the parts are in their neutral or non-operating posi- ,tions (see in full lines in Figures 1 and 3), it maintains the outer surface 90' of lever 90 in engagement with the lower half 97 of the end of the projection 92 on bezel 82. As is clearly seen in Figures 3 and 4, this lower half 97 of the end of projection 92 extends at right angles to the axis of pin or rod 91. The upper half 98 of the inner end of projection 92 is beveled or relieved toward the door side panel 1 and the junction 99 of the surfaces 97 and 98 forms a pivot or fulcrum about which the lever 90 may have limited inward swinging movement.

As best seen in Figure 1, the inner end of bar or lever 80 is rounded at 80' and engages the outer surface of lever 90. In operating the apparatus just described, when the latch mechanism is unlocked and the arm 4 is free to move inwardly into latch releasing position, outward movement of the handle 79 will cause corresponding inward movement of the bar 80 and the engagement of the inner end portion 80' thereof with lever 90 will swing lever 90 in counterclockwise direction (Figure 3) about the pivot point 99 into the phantom line position shown in Figure 3. This pivotal or rotational movement of lever 90 will occur because the force exerted by the preferably preloaded spring 94 against the inner face of lever 90 is sufiicient to hold it against the end of fixed projection 92. Upon releasing the handle 79 under these conditions the spring 94 will straighten out the lever 90 and move it back into its neutral position as seen in full lines in Figure 3 and this movement will be transmitted through the bar 80 to the handle 79 causing it to return to its neutral position as seen in Figure 1. One side of the inner end of bar 80 engages an abutment 100 on the bezel 82 to limit the return movement of handle 79 and also outward swinging movement of lever 90 while engagement of the opposite side of bar 80 with the edge of slot 81 (as seen in phantom lines in Figure l) limits outward movement of handle 79.

When the latch mechanism is locked and the actuating member or arm 4 is blocked against inward movement and the handle 79 is pulled outwardly, the corresponding inward movement of bar 80 will cause the lever 90 to swing inwardly about the point of engagement 101 between the lever 90 and arm 4 and will compress the spring 94 as shown in Figure 4. From the above description it will be seen that when the latch mechanism is unlocked the handle 79 and bar 80 may be moved to effect swinging movement of the contact member or lever about the pivot point 99 formed by the junction of the end surfaces 97 and the arm 4 is blocked against inward movement, movement of the handle 79 into its extended position will cause lever 90 to be pivoted about its opposite end at 101 and the safety spring 94 to be compressed. The limit of outward movement of the handle 79 is reached when bar 80 engages the end of slot 81 and outward force applied to the handle after reaching this position will be taken by the bezel 82 and the door structure. The parts are so proportioned that this position of bar 80 is reached before spring 94 reaches its maximum yielding or fully compressed condition (see Figure 4) and thus it is impossible by movement of handle 79 to exert a greater load on the locked latch mechanism than can be transmitted through the resilient spring 94. In either idling or operating conditions the compression of spring 94 is effective to return the lever 90, bar 80, and handle 79 to their neutral or non-operating positions. Thus spring 94 acts both to return the handle 79 to neutral position (Figure 1) and to serve as a safety spring to permit idling movement of the handle 79 and to prevent excessive force from being applied when the latch mechanism is locked.

It will be noted that in the illustrated embodiment of my invention the movement of the manually operable handle or the like in latch releasing direction is limited by a fixed stop on the frame or housing which is located to be effective to limit releasing movement of the handle before the safety spring reaches its maximum yielding position (the position in which it acts as a solid member rather than as a resilient spring member). As noted above this makes it impossible to overload the latch mechanism.

Although I have described in considerable detail my improved safety handle control mechanism for door latches or the like it will be understood that variations and modifications may be made in the arrangement and proportions of the parts which make up my improved apparatus. Accordingly I do not wish to be limited to the specific form herein shown and described but claim as my invention all embodiments thereof coming within the scope of the appended claims.

This application is a division of prior application Serial No. 8,565, filed February 16, 1948, for Control Mechanism for Door Latches (Patent No. 2,573,679).

I claim:

1. Control mechanism for door latches including a supporting frame structure, a handle supported on said frame structure with the major portion of the handle disposed outwardly of said frame structure for movement between a neutral or non-operating position and an operating or latch releasing position, an operating bar carried by the inner end of said handle, a pin carried by said frame structure and projecting inwardly therefrom, a contact member in the form of a lever apertured to have a loose fit over said pin and be supported thereby, said frame structure having a projection having angularly disposed adjacent end portions from which said pin projects, a spring carried by said pin, and means for retaining said spring in preloaded condition on said pin with one end portion thereof yieldingly holding the inner end of said lever against and aligned with one of said end portions, said operating bar being adapted to engage said lever and move same about the junction of said adjacent end portions as a fulcrum when said handle is moved to latch releasing position and the resistance to movement of the outer end of said lever is less than the force required to compress said spring and move said lever along said pin, movement of said handle and bar to latch releasing position When said outer end of said lever is blocked against movement resulting in movement of the inner apertured end of said lever along said pin away from said end portions of said projection.

2. Control mechanism for door latches including a supporting frame structure, a handle supported on said frame structure with the major portion of the handle disposed outwardly of said frame structure for movement between a neutral or non-operating position and an operating or latch releasing position, an operating bar carried by the inner end of said handle, a pin carried by said frame structure and projecting inwardly therefrom, a contact member in the form of a lever apertured to have a loose fit over said pin and be supported thereby, said frame structure having a projection having angularly disposed adjacent end portions from which said pin pro- 98 of projection 92, while, when.

jects, a spring carried by said pin, means for retaining said spring in preloaded condition on said pin with one portion thereof yieldingly holding the inner end of quired to compress said spring and move said lever along movement of said handle and bar to latch releasing position when said outer end of said lever is blocked against movement resulting in movement of theinner apertured end of said lever along said pin away from said end portions of said projection, and means on said frame structure for stopping movement of said handle and bar in portion of the handle disposed outwardly of the frame for movement between a non-operating neutral position and a latch releasing position, said handle having at its inner end an operating portion projecting inwardly of the frame through a slot in the frame; a latch-operating lever rounding the pin, and, on the end of the pin, adjustably mounted means retaining the safety spring in surrounding relation to the pin.

4. Control mechanism as in claim 3 in which the lever depends from the pin with its longitudinal aXis extending substantially vertically.

5. Control mechanism as in claim 4 in which the lower lendhof the lever extends downward into proximity to the atc 6. Control mechanism for a door latch comprising a prising a unilaterally mounted pin e aperture in the lever, a safety spring surrounding the pin, and, on the end of the pin, means for retaining the safety spring in surrounding relation to the pin.

7. Door latch control mechanism comprising a frame; a handle mounted in the frame with the major portion of the handle disposed outwardly of the frame for movement between a non-operating leasing position, said bearing against the supported end of the lever to bias the supported end of the lever toward the frame.

8. Control against lateral displacement.

ontrol mechanism as in claim 8 in which the pin projects through an aperture in the lever into the void within the resilient means.

References Cited in the file of this patent UNITED STATES PATENTS 2,031,664 Miller Feb. 25, 1936 2,128,535 Lindstrom et al. Aug. 30, 1938 2,382,062 Joachim Aug. 14, 1945 

